Mesocyon ("middle dog") is an extinct genus of the Hesperocyoninae subfamily of early canids native to North America. It lived from the Oligocene to Early...

species. Four major lineages can be defined based on shared characteristics: Mesocyon-Enhydrocyon clade (includes Cynodesmus, Sunkahetanka, Philotrox) Osbornodon...

branch of the Canidae was Hesperocyoninae, which included the coyote-sized Mesocyon of the Oligocene (38–24 Mya). These early canids probably evolved for the...

hesperocyonine canids, with three genera (Parenhydrocyon, Enhydrocyon, and Mesocyon), ranging in size from jackals to small coyotes, appearing in the early...

Ectopocynus (32–19 mya), Osbornodon (32–18 mya), Paraenhydrocyon (20–25 mya), Mesocyon (31–15 mya) and Enhydrocyon (31–15 mya). This genus of primitive canids...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

fragments. A canine dog also known from the Toston & John Day formations. Mesocyon M. robustus Wounded Knee Area. Mandibles. A hesperocyonine dog. "M." temnodon...

slender premolars that clearly contrast with the strong premolars of the Mesocyon–Enhydrocyon group, but also parallels that clade by having a reduced metaconid...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

†Merycoides longiceps †Merycoidodon †Merycoidodon bullatus †Mesocyon †Mesocyon brachyops †Mesocyon coryphaeus †Mesohippus †Mesohippus bairdi – or unidentified...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

Turtle Cove Member. A mostly complete cranium. Reassigned to Hoplophoneus. Mesocyon M. brachyops May be from the Turtle Cove Member. Skull elements & pelvis...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

†Merycoidodon culbertsoni – type locality for species †Merycoidodon major †Mesocyon †Mesocyon temnodon †Mesohippus †Mesohippus bairdi †Mesohippus exoletus †Mesoreodon...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

†Merychippus †Merychyus †Merycochoerus †Merycodus †Merycoides †Merycoidodon †Mesocyon †Mesohippus †Mesoreodon †Metamynodon †Metamynodon planifrons †Michenia...

Caniformia incertae sedis †Prohesperocyon †Hesperocyoninae Hesperocyon Mesocyon Cynodesmus Sunkahetanka Philotrox Enhydrocyon Paraenhydrocyon Osbornodon...

serrator †Merychippus †Merychyus †Merycochoerus †Merycoides †Merycoidodon †Mesocyon †Mesohippus †Metalopex Metasequoia †Metasequoia occidentalis †Microphallus...

†Merychippus †Merychyus †Merycochoerus †Merycodus †Merycoides †Merycoidodon †Mesocyon – report made of unidentified related form or using admittedly obsolete...